Alipay has followed WeChat's lead and said it will start charging users who pay their credit card bills through the app starting next month.

Alipay users will be required to pay a service fee of 0.1 percent on credit card payments above 2,000 yuan (US$294) each month, according to a statement from Alipay today.

For example, if an Alipay user intends to repay a credit card bill of 3,000 yuan, it'll cost him or her an extra commission of 0.1 percent on 1,000 yuan, or 1 yuan.

It explained that the move was made to address rising operation costs and that the new rules will take effect on March 26.

Alipay and WeChat's digital wallet are two leading payment tools in China's mobile payment sector, and have grown beyond processing online payments to include more offline merchants when people are shopping or paying for services. Users can link their credit cards and debit cards to their account and can also use their account balance for online and offline payments.

"We understand that trying our best to make ends meet would do no good for our long-term sustainable development, and we'll strive to provide better services in the future," it said in a statement.

Alipay users can also use their membership credits to raise the free-of-charge threshold each month.

Most domestic commercial banks allow users to repay their credit card bills from their debit accounts free of charge, and sometimes also provide subsidies for credit card bills from a different bank.

WeChat began to charge a service fee of 0.1 percent for credit card bill repayment in August last year, and offers no free-of-charge threshold.

It explained that its digital wallet service has been subsidizing the commission charge for each credit card repayment transaction and the operation cost has climbed as quickly as usage picked up.

Some also argued that the move was intended to promote Alipay's virtual credit service Huabei.